Selectively openable ports are used in the downhole drilling and completions industry for enabling fluid communication between tubulars, annuli, etc., in a variety of applications. Some systems use one or more slidable sleeves for providing the selective control of the ports. One way of increasing the pressure rating of the system is to increase the wall thickness of the components of the system. However, this can become very expensive and result in the need for a larger borehole or an unnecessarily large usage of radial space. As a result, the industry always well receives new port control systems having improved pressure ratings.